Bioacoustics of Myopsalta leona

Distribution, habitat and behaviour ( Fig. 11 ). Myopsalta leona is found south from the tropic of Capricorn in western, southern central and inland south-eastern Queensland from the eastern edge of the Simpson Desert south-east to the Lockyer Valley west of Brisbane. It also occurs in inland New South Wales from Narrabri west to Lightning Ridge and south to Goolgowi. Populations occur in acacia-dominated woodland and shrubland, as well as dry, temperate eucalypt woodland where the adults are typically found on the branches and in the foliage of trees and larger shrubs. Adults have been encountered from October to March. They have occasionally been observed in very large numbers, spreading from vegetation on to nearby wooden power poles and fence posts. Calling song ( Figs 13 , 14 ). The song of this species contains repetitive buzzing phrases, each with a brief inflection in amplitude and frequency towards the middle. Each phrase commences with a long echeme, typically with a duration of 2.018– 3.954 s , followed by a brief gap (0.004– 0.021 s ) and a syllable or macrosyllable of 0.011– 0.029 s duration (all statistics, n= 17 recordings). Close inspection of the structure within the long echeme sometimes reveals that the beginning contains a series of discrete syllables, or alternatively it may be entirely coalesced. The inflection occurs in the long echeme, typically half way to two thirds into its overall duration. The highest point of inflection can reach up to four times the amplitude of the beginning of the echeme and may be sustained at this increased volume for up to 0.6 s . Observations indicate that the inflection is cause by a marked upward contraction of the abdomen, followed by partial relaxation. Generally, the amplitude remains slightly higher relative to the beginning of the echeme for the remainder of the echeme following the inflection. Prior and following to the inflection, the calling song typically exhibits a highest amplitude frequency plateau between 11.2 and 18.4 kHz. This increases to 13.0–19.5 kHz, or slightly higher, during the inflection. Some geographic variation is evident in calling song, with larger specimens from central New South Wales exhibiting slightly extended long echeme (up to 5.91 s ) and lower frequency plateaus (8.7–15.2 kHz before inflection and 11.4–17.0 kHz at inflection). In addition, in recordings from Cravens Peak at the western edge of the species’ distribution, produce slightly shorter long echemes (1.417– 1.510 s ) and the inflection is produced earlier than in other examples ( Fig. 14A ).

Calling song (Figs 13, 14). The song of this species contains repetitive buzzing phrases, each with a brief inflection in amplitude and frequency towards the middle. Each phrase commences with a long echeme, typically with a duration of 2.018–3.954 s, followed by a brief gap (0.004–0.021 s) and a syllable or macrosyllable of 0.011– 0.029 s duration (all statistics, n= 17 recordings). Close inspection of the structure within the long echeme sometimes reveals that the beginning contains a series of discrete syllables, or alternatively it may be entirely coalesced. The inflection occurs in the long echeme, typically half way to two thirds into its overall duration. The highest point of inflection can reach up to four times the amplitude of the beginning of the echeme and may be sustained at this increased volume for up to 0.6 s. Observations indicate that the inflection is cause by a marked upward contraction of the abdomen, followed by partial relaxation. Generally, the amplitude remains slightly higher relative to the beginning of the echeme for the remainder of the echeme following the inflection. Prior and following to the inflection, the calling song typically exhibits a highest amplitude frequency plateau between 11.2 and 18.4 kHz. This increases to 13.0–19.5 kHz, or slightly higher, during the inflection. Some geographic variation is evident in calling song, with larger specimens from central New South Wales exhibiting slightly extended long echeme (up to 5.91 s) and lower frequency plateaus (8.7–15.2 kHz before inflection and 11.4–17.0 kHz at inflection). In addition, in recordings from Cravens Peak at the western edge of the species’ distribution, produce slightly shorter long echemes (1.417–1.510 s) and the inflection is produced earlier than in other examples (Fig. 14A).